Mutation of albedo and growth response produces oscillations in a spatial Daisyworld
- Event time: 1:00pm
- Event date: 21st November 2005
- Speaker: Jamie Wood (University of Edinburgh)
- Location: Room 2511, James Clerk Maxwell Building (JCMB) James Clerk Maxwell Building Peter Guthrie Tait Road Edinburgh EH9 3FD GB
We present an extension of a 2-dimensional cellular automata (CA) Daisyworld to include mutation of optimum growth temperature as well as mutation of albedo. It is well established for only the latter case that such models exhibit homeostasis of the environment temperature in this case. In our model the organisms (daisies) can adapt to prevailing environmental conditions or evolve to alter their environment. This setup therefore allows us to examine whether or not the former inhibits or even destroys the homeostatic effect. We find the system to be capable of regulation on average but that it oscillates with a period of hundreds of daisy generations. The ability of the daisies to alter their optimal growing temperature leads initially to a planet which is less able to sustain itself, but the planet becomes steadily more stable (on average) for greater rates of genetic drift in this characteristic. Weaker and less regular oscillations have already been predicted in Daisyworlds before but in this model they become stronger and more regular as the mutation rate of the optimum growth temperature is increased. This demonstrates that long period oscillations can be generated internally by even highly simplified earth models. Here a new timescale is induced by including evolutionary dynamics, a effect not normally included in such models.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..